A gas turbine engine generally includes, in serial flow order, a compressor section, a combustion section, a turbine section and an exhaust section. In operation, air enters an inlet of the compressor section where one or more axial or centrifugal compressors progressively compress the air until it reaches the combustion section. Fuel is mixed with the compressed air and burned within the combustion section to provide combustion gases. The combustion gases are routed from the combustion section through a hot gas path defined within the turbine section and then exhausted from the turbine section via the exhaust section.
In particular configurations, the turbine section includes, in serial flow order, a high pressure (HP) turbine and a low pressure (LP) turbine. The HP turbine and the LP turbine each include various rotatable turbine components such as turbine rotor blades, rotor disks and retainers, and various stationary turbine components such as stator vanes or nozzles, turbine shrouds, and engine frames. The rotatable and stationary turbine components at least partially define the hot gas path through the turbine section. As the combustion gases flow through the hot gas path, thermal energy is transferred from the combustion gases to the rotatable and stationary turbine components.
A typical gas turbine engine includes very fine cooling passages that allow for higher gas temperatures in the combustor and/or the HP or LP turbines. During operation, particularly in environments that contain fine-scale dust (e.g. PM 10), environmental particulate accumulates on engine components and within the cooling passages of the engine. For example, dust (reacted or non-reacted), sand, or similar can build up on the flow path components and on the impingement cooled surfaces during turbine engine operation. In addition, particulate matter entrained in the air that enters the turbine engine and the cooling passages can contain sulphur-containing species that can corrode the components. Such accumulation can lead to reduced cooling effectiveness of the components and/or corrosive reaction with the metals and/or coatings of the engine components. Thus, particulate build-up can lead to premature distress and/or reduced engine life. Additionally, accumulations of environmental contaminants (e.g. dust-reacted and unreacted, sand, etc.) such as these can degrade aerodynamic performance of the high-pressure components and lower fuel efficiency of the engine through changes in airfoil morphology.
Accordingly, the present disclosure is directed to a system and method for cleaning engine components using abrasive particles that addresses the aforementioned issues. More specifically, the present disclosure is directed to a system and method for in-situ cleaning of engine components that utilizes abrasive microparticles that are particularly useful for cleaning internal cooling passages of the gas turbine engine.